New Research in the U.S. Shows Widespread Shrinkage of Gray Matter in Women’s Brains During Pregnancy
The study tracked changes in brain structure during pregnancy by imaging a woman’s brain before, during, and up to two years after childbirth.
Pregnant women’s bodies undergo many changes to prepare for motherhood – (Photo: Getty Images).
According to ScienceAlert on September 17, a group of American neuroscientists conducted 26 MRI scans of a healthy 38-year-old woman who became pregnant through IVF. The results of the MRI scans revealed widespread reorganization in the mother’s brain, including some short-term changes and some long-lasting changes over the years.
The most noticeable change was the consistent reduction in both the volume and thickness of gray matter (the brain’s wrinkles) throughout pregnancy, with neural connections peaking temporarily at the end of the second trimester (the middle three months of pregnancy).
Specifically, during pregnancy, more than 80% of the gray matter in the examined brain regions shrank by an average of 4%, although everything returns to normal after pregnancy. This 4% decrease is comparable to the reduction seen during puberty.
The increase in hormones during puberty is accompanied by a decrease in gray matter as the brain eliminates excess tissue to function more efficiently. According to Emily Jacobs, who works at the University of California, Santa Barbara (UCSB) and is the lead co-author of the study, a similar process may occur during pregnancy.
The brain loses some wrinkles (gray matter) during pregnancy – (Photo: Laura Pritschet).
According to the research team, while the shrinkage of gray matter may sound alarming, these changes are likely beneficial as they may reflect a limited reorganization of brain tissue in preparation for motherhood.
Additionally, the study noted that the microstructure of white matter (a measure of the brain’s nerve system) peaked in size at the end of the second trimester before decreasing. Cerebrospinal fluid and brain cavities (ventricles) also increased in size. These changes are associated with rising hormone levels.
This research paves the way for a much deeper understanding of the pregnant brain during pregnancy. It also marks the launch of the Maternal Brain Project, an international effort to collect more similar brain scans from more pregnant women, according to The Guardian.
The research team is conducting MRI scans on other pregnant women to better understand the risks of postpartum depression, the relationship between preeclampsia and postpartum memory loss, and why pregnancy may help reduce migraine symptoms and symptoms of multiple sclerosis.
So far, only a few studies have explored what happens to the brain during pregnancy. In 2017, researchers showed that pregnancy coincides with a significant decrease in gray matter.
